Shock absorber



` Jan.' 3, 1.928.`

vJ. A. STEVENS SHOCK ABSORBER Filed Sept. 9. 1926 v 2 Sheets-Sheet 11,655,205 '.J. A. STEVENS SHOCK ABSORBER Filed Sept. 9. 1926 2Sheets-Sheet 2 f77/06771277" 'fa/@72,2% .'tevez' @M www? j 4 dfyzPatented Jan. 3, 1928.

UNETED STATES PATENT OFFICE..

JOHN A. STEVENS, OE? LOT/WELL, MASSACHUSETTS, ASSGNOR TO STEVENSPRODUCTS COMANY, GE LOWELL, MASSAC USETTS, A CGRPORATION OF DELAWARE.

SHOCK ABSORBER.

Applicatonled September 9, 1926. Serial No. 134,403.

This invention relates to devices tor a-bportion et adapted to enclose apiston rod soibing shocks caused by the quick relative screw threaded oneither end. A sleeve 6 .nuivcment ot two members. As one of the havinginterior threads engaging the lower most conunon uses ot such devices isin conthreaded end ot the rod 5 lias on 'its exterior '5 nection withautomobiles to absorb the surface a Shoulder 'l' toi-ming a seat tor the60 shocks caused by the unevenness ot the road coil spring 9 surroundingthe piston rod 5 by the insertion of the device between the and mountedbetween said shoulder and an chassis and springs, an embodiment ot theannular inturned abutment 10 which may invention usable tor this purposeis specitibe made integral with the body portion L1.

10 cally set forth in the Yfollowing description, Surrounding the upperend ot' the body por- 65 but it is to be understood that this is notintion et and suitably attached thereto as, for tended to be in anymanner limiting on the example, by screw threads 11 is a substanscopeoic the invention. tially spherical casing or dome l2 having a At thepresent time automobiles and other Chamber 13 therein.

15 motor vehicles are constructed to absorb the Enclosed within thecasing 12 is an inner 70 lighter shocks so that the occupants thereofcasing or carcass of rubberized fabric or are only subjected to shocksot greatest inother flexible material containingl an inner tensity, andthose are softened so that a rolllining ot' rubber or other suitablematerial ing or oscillatory motion is all that is transboth of which arehere indicated diagrammitted to them; however,'when going at maticallyat 14. The casing 14 is adapted 75 high speeds or over rough roads, andin any to be inflated through a suitable valve 1G case when travellinglong distances, eventhis attached to the casing and extending becomesdisagreeable. It is one of the obthrough the top ot the cylinder 12, thevalve jects ot this invention to overcome this dis- 16 being of any kindcommonly employed agreeable motion lirst, by cushioning the iniinconnection with pneumatic casings. The 8e tial shock, and second, byslowing up or upper end ot the piston rod 5 extends dampening therebound. This second acthrough an opening 17 in the abutment 1() tion isespecially important in the case of and into the dome 12 and carries'asupport automobiles equipped with balloon tires or head 18 thereon whichmay be attached which themselves act as shock absorbers, but thereto inany suitable manner, as for eX- 85 do not stop the objectionableoscillatory moample, by ordinary screw threads. As the tion abovedescribed. Other objects and adpiston rod 5 is threaded into both thesleeve vantages of the invention willl be apparent 6 and the head 18, itis obvious that by propas the description proceeds and will be parerlyscrewing the parts together the tension ticularly pointed out in theappended of springs 9 and 19 may be varied. 90 claims. The support 18bears against the lower Referring to the drawings in which are side ofthe casing 14: and, as is obvious, will shown several embodiments oft-he invenfurther compress the iluid in the comprestion: sion chamber 13on upward movement. A 40 Fig. 1 is a view substantially in vertical coilspring` 19 which may be ol' smaller 95 section oi the device; gauge wirethan spring 9 is arranged be- Fig. Q is a substantially similar view ofa tween the abutment 1() and the lower side ot modiiication of thedevice; and the support 18 encircling the piston rod.

Fig. l is a similar view ot a iiurther modi- This spring provides avariable resilient relication. sistance against downward movement of 100Referring to the embodiment oi the dethe support or head 18. vices shownin Fig. 1, the numeral 1 desig- A combined butter and check springsupnates the usual semi-elliptic leaf spring porting` device is providedon the piston rod mounted on the axle of a vehicle and adapt- 5 on oneside vof the abutment l0. This deed to support the usual chassis ortraine 2. vice may comprise a nut 21 threaded on the 105 In accordancewith this invention a shock piston rod and locked in any desiredposiabsorbing device, designated as a whole by tion by thecheck or locknut 9.2. Supported the numeral 3 is inserted between one end on nut 21is a relatively short but heavy ot the leat spring 1 and the body ortrame 9.. spring' 2O which. normally terminates short l5t The shockabsorber 3 comprises body oi the abutment 10, and has the function ot110 y heafvv slioclris,sustained by the vehicle, and

is also useful in the event of failure ot' either the pneumatic casing'14s or the spring. 9.

A somewhat snnilar buffer or resilient stop kis provided on the otherside ott the abut- P il iti

nient 1,0, which in this case comprises a nut 2l', which may be suitablyspaced from the headglj-byra washer122 or other spacing Vdevice andwhich is provided on .its lower portion. with 'a short spring 20 similarto.

spring` 20. The springs 2O and Q0 may be retained against nuts 21 and21. respectively bynieans of flaring; extensions 21 on cach of the nutsengaging' the endmost turn et thespring. .The springl has a functionsomewhat analogous to spring' 20 in that it is desigiiedto cushion therebound troni extremely heavy shocks only, thus act-ing: in tandem withspring' 19. It will be seen that bothV springs 20- and 20 are normallynot in operation but are etlective only to vcushion extremely heavyshocks and rebounds respectively. Y y

The casing is provided abovethe abutnient 10 with a suitable breather 23whichA may be constructed with an expanding nipplegtthreaded yorotherwise secured in a suitable aperture in the side of casing 4 andvprovided on its inside with a screen 25. A perforated cover 26 may besecured in any desired manner to the nipple 24 and confine betweenv itand the screen 25 any suitable.

packing` material as, for example, wool,

VThis breather may servealso as a drain for any liquid which'niightcollect within the casina. y.

The ,casing'l is rigidly `held to the chassis 2 in any suitable manneras, for example, .by a plate 27 which may be attached to the casing Libybolts 28 and pivoted to the end ot thevchassis-Q as shown at 29.- Thecasingt is provided above the point ot attachment of the plate 27 with asuitable biturcated lug 30 which is attached by means ot anarm 3l to asul'istitute clamp or connecting' ineinber 32 bolted or riveted as shownat to the chassis 2. VThe casing` ft is also provided with a strut orbumper connection 34. l,

'A lever 35 is pivoted adjacent yto the lieti tom ot casini;y d as at 36and ispivoted at its other end to the springs 1 as shown at 3T.Intermediate its ends the lever 35 is pivotally connected as .sh-own'at38 to the sleeve 6 which isfattached to t-lie lower end ol: the rodHence it will be seen that as only one end of the rod 5 is positivelyconnected to a mechanical Velement either stationary or moving in apredetermined path, it is substantially unguided, Tliisfresultsinmizing. friction as there are few Vplaces where one part has a rubbingor sliding contact with another part and consequently the device willwear indelinitely.

The operation ol the device is as follows: llhen the wheels ot thevehicle hit an unevent point in the road, the first action is thatpivotal points 29 and S7, Vot' the chassis and springs respectively,approach each other thereby rocking the lever 35 in a countercloclrwisedirection, `forcing` the rod 5 upwardly. This move-ment compresses thespring' 9 andsimultaneously causes the head 16 to engage the casing, 14,whereby the air or other fluid in thechamber 13 is compressed thuscushioning and absorbing the shock. On the rebound, the downwardmovement of the r'od 5 is slowed up by compression -ot the spring` 19,thus effectively tending to neutralize and reduce the oscillatorytendency otherwise present.

Referring to Figs. 2 and 3 the device consists oi a casing; having; anintegral arm 51. thereon which is adapted to be'connected to the chassisotan automobile atlpoints 52 and 53 in somewhat the same manner as thedevice shown in Fig. 1 is adapted to be connected tothe chassis 2 asshown at points 29 and 30; A rockerarm 54 ispivoted to the casing 50 at55 and is adapted to havea ypoint 56 thereon connected to the usual vsprings oit the vehicle. An intermediate point 57 ot the rocker armvcarries a piston lgenerally indicated at 58 comprising a sleeve member59 having a shoulder 60 at its lower portion and being' internallythreaded for engagement with a piston rod 61.r The casing' 50 isprovided with an inwardly directed abutment or flange 62, and between thisVsleeve engagingrthe yendinost turn of the spring. Spring 6ft normallyterminates short of the abutment 62,7whereby this spring is .normallyout et operation; hiitit becomes effective on au extremely heavy shockor in the event an extremely heavy load is placed up-on the device,toact in tandem with spring 63 in opposingr movement ol the pis a ton iuan upward direction.

` The rod (il .is provided at its upper end' with a collar which is heldin any predetermined adjusted position by a pair of nuts 66 and 67. IAsomewhat similarcollar 68 is fastened to the abutment- 62 by a pluralityof screws 69.v Collars 65 and'68 are each provided with an annularvgroove ot,

substantially theV same width andldiameter and facing` each other. Inthe embodiment Of the device "shown in Fig. 2 a spring 70 Lik) is placedin the grooves of members 65 and 68 and tends to hold these collarsapartthereby opposing movement of the rod 61 in a downward direction,the recoil from the initial shock being taken up thereby. In theembodiment illustrated in Fig. 3 an annular member 71 of resilientmaterial, such as rubber, may be inserted in the grooves of members 65and 68 in place of' the spring 70 shown in Fig. 2. This member undernormal compression is deformed in the manner shown in Fig. 3 so that itis bulged 4both out-wardly and inwardly in the space between thecollars. Its function is, however, exactly the same as that explained inrelation to Fig. 2. Nuts 66 and 67 may be adjusted to any desiredposition along the rod 61 thus varying the effective resistance of thespring 70 or the resilient rubber member 71 in a manner similar to thatin which the load on spring 19 (Fig. 1) may be varied and forr the samepurpose, that is, to vary the resistance of the device to shocks inrecoil from the initial shocks.

A dome 72 is ordinarily used in connection with the device to preventdust and other foreign material from becoming lodged therein, the domebeing held in position in any suitable manner not shown in detail on thedrawings and being provided with an extension 73 at its top, which mayserve both as an ornament and as a means to permit gripping the dome inthe event that the dome is screw threaded onto the body 50 of thedevice.

I do not wish to be limited to the shape, size or construction of theembodiments of the invention here shown, but merely by the scope of theappended claims.

l claim:

1. A device for absorbing the shocks caused by the quick relativemovement of two members, comprising a casing fixed to one of saidmembers, a lever pivoted to the other of said members and to a part ofsaid casing, cushioning means having a rod pivoted to said lever andadapted to oscillate within said casing, an abutment within said casingadjacent to the rod, shoulders on the rod spaced from said abutment,springs surrounding said rod on either side of said abutment between itand said shoulders to absorb both the initial shock and the recoil, andan additional spring fixed to one of said shoulders and normallyterminating short of said abutment, whereby said additional spring iseective to absorb only an extremely heavy shock.

2. A device for absorbing the shocks caused by the quick relativemovement. of two members comprising a casing fixed to one of saidmembers, a lever pivoted to the other of said members and to a part ofsaid casing, cushioning means having a rod pivoted to said leverandadapted to oscillate within said casing', an abutment within said casingadjacent to the rod, shoulders on the rod spaced from said abutment,springs surrounding said rod on either side of said abutment between itand said shoulders to absorb both the initial shock and the recoil, andadditional springs fixed to both of said shoulders and norn'iallytern'iinating short of said abutment, whereby said additional springsare effective only on an extremely heavy shock to cushion and absorbboth the initial shock and the recoil.

A device for absorbing the shocks caused by the quick relative movementof two members comprising a compression member having a casing fixed toone of said members, said compression member containing a compressiblefluid, a lever pivoted to the other of said members and to a part of'said casing, a rod pivoted to said lever and operatively connected tosaid compression member, whereby movement of the rod in one directionwill be opposed by increased pressure of the fiuid in said compressionmember. lan abutment adjacent to said rod, a shoulder on said rod, and aspring fixed tc said shoulder having its end. normally spaced from saidabutment and effective only on an extremely heavy shock for cushioningand dampening movement of said rod in the opposite direction.

4. A device for absorbing the shocks caused by the quick relativemovement of two members, comprising a compression member having a.casing fixed to one of said members, said compression member containinga compressible fluid, a lever pivoted to the other of said members andto aV part of said casing, a rod pivoted to said lever and adapted tooscillate in said casing, an abutment adjacent to the said rod,shoulders on said rod, a spring extending from one of said shoulders tosaid abutment and acting in tandem with saidicompression member tooppose movement of said rodi in one direction, an additional springfixed to each of said shoulders and normally terminatingr short of saidabutment, the additional springs being effective only for an extremelyheavy shock to opposeextreme movement of said rod in either direction.

5. A device for absorbing the shocks caused by the quick relativemovement of two members, comprising a compression member having a casingfixed to one of said members, said member containing a compressiblefluid, a lever pivoted to the other` of said members and to a part ofsaid casing, a. rod pivoted to said lever and adapted to oscillate insaid casing, an abutment adjacent to said rod, shoulders on said rod, a,spring extending from one of said shoulders to said abutment to act intandem with said compression member in opposing movement of said rod inone direction, a second spring extending from the other shoulder tothemember having ay casing ixed to one otsaid members,y said membercontaining a compressible fluid, a lever pivoted to the other of saidmembers and to a part oiisaid casing, a rod pivoted to said lever andadapted to oseillate in said chamber, au abutment adjacent to the saidrod, shoulders on said rod, a spring extending from one' of saidshoulders to said compression member to act in tandem' with saidcompression member in Opposing movement of said rod `in one direction, asecond spring extending trom the other shoulder to the abutment opposingVmovement of said rod in the opposite direction, an additional springlixed to each of said shoulders and normally terminating short of saidabutment, the additional springs being effective only on an extremelyheavy shock to oppose extreme movement of said'rod in either direction.l

A Adevice for absorbing the shocks caused by the 'quick relativemovement of two members comprising a casing ixed to one of said members,acompression member Within said casing', saidl compression membercontaining a eompres'sible fluid, a lever pivoted to the'other or saidmembers and toa parteiA said casing, a rod pivoted to said lever andadapted to oscllate Wit-hin said easing, Wherebymovement of therod inonedirection Will be opposed by increased pressure of the iuid in saidcompression n1ember, an abutment adjacent to -the said rod, a. shoulderon said rod, a spring extending between s'aid shoulder and saidabutment, and a second spring iXed to said shoulder having its endnormally spaced from said abutment and elective only on an extremelyheavy shock when both said springs act in tandem to oppose movement o'lthe rod in the opposite direction.

Signedby me at Lowell, Massachusetts this 30th day ot' August, 1926.

Y p JoHN A. srn'vnns.

